Figure 3.

Anisotropic connectivity in PDMS topographical cultures revealed by immunostaining

(A) Representative immunohistochemical images of neurons grown on PDMS topographical tracks at DIV 14, providing a broad overview (left) and a detail (right). For the overview, images show neuronal processes in green, astrocytes in red and cell nuclei in blue, with focus at the top part of the topography, the bottom part, and a combination of them. For the detail, images correspond to the top part of the design only and depict neuronal process (green), astrocytes (red), and the combination of these channels with cell nuclei (blue). Neuronal connections are more abundant in the direction of the tracks than transverse to them. White arrows mark neuronal processes that follow the edge of the topographical design.

(B) Corresponding images for the squares configuration at DIV 14. Connectivity is abundant at the bottom part of the square designs, shaping small microcircuits by themselves that interconnect with the top part.